If you're talking about the cam phasing in relation to piston/crankshaft position (degreeing the cam), here are a couple of videos explaining the procedure....
https://www.youtube.com/watch?v=7cNoVRLb73c
https://www.youtube.com/watch?v=bcMuttJ9RFc
https://www.youtube.com/watch?v=-VwsbEg7Z4I

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